This invention relates to an electronic card receiving device for receiving a card in which integrated circuits are incorporated to have electronic functions, which is referred to as an "electronic card" hereinafter, and more particularly to a card inserting and removing mechanism for the electronic card receiving device.
As the integrated circuit technique has been developed in recent years, it has become to realize integrated circuits on a great scale in a small chip, so that various kinds of electronic cards having high degree functions have been developed so as to be used in wider applications.
FIG. 1 illustrates one of such an electronic card which comprises a non-volatile memory a, i.e. ROM or RAM capable of electrical writing and reading, a central processing unit (CPU) b for controlling operations of the ROM or RAM, a substrate c in the form of a card in which the ROM or RAM and CPU are embedded, contacts d for connection with external electronic instruments. When such an electronic card is used, it is inserted into an electronic card receiving device attached to an external device of an electronic computer or its terminal equipment.
FIGS. 2a-2d schematically illustrate a construction of an electronic card receiving device which has been widely used, showing respective conditions, before insertion of a card (FIG. 2a), during insertion (FIG. 2b), just inserted and electrically connected (FIG. 2c), and during removal of the card (FIG. 2d).
The electronic card 216 is inserted into the receiving device in a direction shown by an arrow A as shown in FIG. 2a. The card 216 is advanced into the device, pushing downward a card guide 221 as shown in FIG. 2b. As a result, a card latch 220 moves downward together with the card guide 221, so that contacts 226 in the form of rods of a circuit board 227 attached to the card latch 220 move downward away from a surface of a card holder 215. FIG. 2c illustrates when the electronic card 216 has completely passed by the card guide 221 and has been received in a card receiving chamber. At this moment, the card latch 220 is raised by a spring force of a spring 231, so that the card guide 221 closes an inlet of the card receiving chamber, and the card 216 is fixed in position with respect to the card holder 215 by a reference surface 222 of the card guide 221 cooperating with the urging spring 231. Moreover, as the card latch 220 has been raised, the rod-like contacts 226 of the circuit board 227 attached to the card latch 220 extend beyond the surface of the card holder 215 so as to be connected to contacts of the electronic card to obtain a condition ready for communication.
When it is desired to remove the electronic card from the card receiving device, a reject key 235 extending out of a housing 201 of the device is pushed in a direction shown by an arrow in FIG. 2d. By depressing the reject key 235, the card guide 221 and the card latch 220 start to move downward as shown in the drawing, so that the contacts 226 of the circuit board 227 attached to the card latch 220 move also downward away from the contacts of the card 216 below the surface of the card holder 215. Further, when the card guide 221 is lowered at the level of the surface of the card holder 215, the electronic card 216 is pushed out of the device by a spring force of a leaf spring 233 provided in the card receiving chamber.
The hitherto widely used electronic card receiving device above described has such superior functions that when the electronic card is being inserted thereinto or removing therefrom, the contacts of the electronic card and the device do not rub each other and when the electronic card is once accommodated in the device, the card is securely fixed in position relative to the card holder 215 with the aid of the leaf spring 233 and the reference surface 222 of the card guide 221.
However, the device of the prior art as above described which solves various problems has still further problems as follows.
In the prior art of the card receiving device as above described, when an electronic card is removed from the device, the card latch 220 is pushed down by manually pressing the reject key 235 to move the electronic card 216 out of the device with the aid o the leaf spring 233.
With this arrangement, the electronic card 216 is pushed out of the device as soon as the reject key 235 is pressed. On the other hand, the reject key 235 is often pressed, for example, during writing or reading of the ROM and RAM in the electronic card or the reject key 235 is frequently unintentionally pressed, so that such a mishandling causes the ROM and RAM to be damaged or at least the contents of the ROM and RAM to be abnormal.
Moreover, the electronic card is pushed out of the device by means of the leaf spring 233. However, it is difficult to provide a long stroke distance of the leaf spring 233. If a distance by which the electronic card is moved out of the device is made sufficient, the leaf spring is subjected to an overload which would prematurely fatigue the leaf spring.